This column tries to answer some of the most commonly asked questions about recycling, composting and the town's solid waste program.

Q: As my incandescent light bulbs burn out, I'd like to start replacing them with those "energy saver" fluorescent spiral bulbs to decrease the amount of electricity used. However, those bulbs contain mercury. I'm not sure how to determine which is worse, more electricity with the conventional bulbs or having to dispose of a mercury bulb. I assume that they are collected at the hazardous waste site.

A: The usual response to this dilemma is to point out that mercury is let loose into the air by coal-fired power plants, so by using less electricity, less mercury is emitted. How much mercury is in the coal varies, depending upon its type. Estimates are that 33 percent of mercury emissions in the U.S. are from coal-fired plants. Lots of electric power in Massachusetts comes from other sources - nukes, gas powered, etc. - so the amount of coal mercury each of your incandescent bulbs causes to be released is pretty small. Estimates for the percentage of Massachusetts electricity that will be generated in a coal-fired plant in 2005 vary from 12 to 16 percent, down from 18 percent in 2000. Of course almost all electricity use causes some pollution, so you're cutting back on that by using the saver bulbs.

The new bulbs have less mercury than the old style, but any fluorescent bulb should be treated as hazardous waste and taken to the drop-offs at Hartwell Avenue. The first collection day this year will be April 30th. There are services that take fluorescents away from large corporate buildings for recycling but they probably don't come to private homes.

Q: I want to get rid of an old toaster. It is an appliance or can I just put it into the trash?

A: A toaster can go in your regular trash if you really want to throw it away. There is a fix-it shop at the Senior Center on Thursday mornings. Possibly you could get it repaired. If it still works and you're getting rid of it because you no longer want it for some other reason, you can donate it to Goodwill (there is a donations truck behind Walgreens, and other places A microwave oven is regarded as an appliance and you would have to call Waste Management for a pickup appointment, but the toaster doesn't count as an appliance. '

Reminder from the DPW: Residents can continue to bring' their Christmas tree to 201 Bedford St. The next CRT collection is scheduled^, for April 9.